Heat motor



March 21, 1933. M. PERSONS HEAT MOTOR Original Filed June 15, 1925M1216?! [We/w 7/4 222/6716 ,41%; g7 a a Pmmd Mar. 21, 1933 UNITED STATESPATENT orrlcr.

LAWRENCE M. PERSONS, O! DES KOINES, IOWA, ASSIGNOB TO COOK ELECTRIC COK-PANY, OF CHICAGO, ILLINOIS,

A CORPORATION 01 ILLINOIS HEAT MOTOR Continuation of application SerialNo. 87,091, filed June 15, 1925. This application flied January 10,1889. Serial No. 331,890. Renewed January 27, 1833.

My invention relates to thermally controlled vapor motors and more(particularly to a vapor motor of this type a apted to be influenced bythe thermal expansion of a volatile fluid.

Va or motors constructed in a manner to be in uenced by thethermalexpansion of a volatile fluid usually consist of an expansible andcontractible vessel cooperating wit a suitable source of heat arrangedto heat the fluid and increase the pressure within the vessel. Numerousfactors obviously enter into the timing of the movement of the vessel.It has been found that after the initial movement. the vessel continuesat a rather rapid rate to expand. but considerable difliculty is exerienced in avoiding an undesirable lag iiefore the initial movementbegins. On the other hand, it is difiicult, due to this initial timelag, to thereafter control the movement in proper timed relation, whichis not only desirable but essential in the operation of variousregulators.

One of the objects of the present invention resides in the provision ofan improve form of vapor motor having a heating tube or boiler incommunication with an expansible and contractible vessel and a source ofheat which are so arranged as to first rapidly volatilize a limitedamount of the liquid, thereb rapidly increasing the pressure within tlie vessel and accelerating t e initial movement of the vessel.

More specifically, this result may be accomplished by arranging theelectrical resistance wire or heat coil about the tube or boiler so thatthe turns of the heat coil are spaced more closely together at the upperend where the volatile liquid first starts to ex and. Accordingly, thepressure in the tn 0 or boiler rapidly increases at the startandthereafter builds up more uniformly and quickly.

I have found that by providing approxi mately three times the number ofturns of the heat coil at the upper end of the tube. it is possible tosecure complete predetermined expansion of the vessel in one-third ofthe time heretofore required.

Other objects and advantages of the in vcntion will be apparent from thefollowing description when taken in connection with the accompanyingdrawings in which:

Figure 1 is a view partly in section and )artly in elevation of a heatmotor embodymg my invention;

Fig. 2 is a similar view of another embodiment of my invention; and

Figs. 3 and 4 are also similar views illustrating difierent embodimentsof the invention.

In the drawings wherein for the purpose of illustration there are shownseveral preferred embodiments of my invention, the vapor or heat motormay comprise an expansible and contractible vessel 1 having a volatileliquid therein and atube 2 or boiler in communication with the vesseland which receives a portion of the liquid.

This vessel 1 is preferably shown as comprising a well known form ofbellows which readily expands or contracts upon an increase of (pressuretherein. Tube 2 is closed at one on posite open end with vessel 1. Asto. the specific form of heating device that may be used, it is obviousthat the source may be an electrical resistance coil or heating flameconveniently located at or adjacent to tube 2. A heating zone will beprovided within tube 2 for heating the volatile liquid and driving itinto vessel 1 by volatilization. The pressure within the tube will begradually increased until the level of the liquid is depressed.whereupon further volatilization stops as the liquid is driven out ofthe heating zone. It is by this means that a predetermined expansion ormovement of vessel 1 may be efi'ectively obtained and held withoutdanger of the pressure within building up to a point where the vesselwill burst. In so far as this subject matter is concerned the presentapplication is a continuation of copending application Serial No.37,091, Filed June 15. 1925.

The vapor motor shown. in Fig. 1 includes the expansible andcontractible vessel I having one end closed by a plate 3 to which may beattached a movable actuating rod 4, if this end of vessel is a ranged tobe movand in communication at the op-.

able.

A late 5 suitabl closes 0B the opcm of vessel 1, t is plate beingprowith an opening Ginto which is seated cup 7 that-may ex tendinto-vessel 1. Cup 7 may then extend upward-1y by means oia neck 8. Thisneck 8 communicates with the lower open end of tube 2 and ishermetically scaled thereto at 9.

A sheet of mica 10, ;or other suitable insulation, may be wrapped abouttube'2 so as to provide electrical insulation for an electricalresistance wire or heat coil 12 wound about the tube. Terminal bands 13and 14 are clamped at proper points along tube 2 to receive the ends ofheat C011 12. While I have shown a heat coil of an electrical circuitfor furnishing heat or acting as a source of heat for the vapor motor,it will be un derstood that any suitable heating means may be employed.

I find that by applying the heat to tube 2 in a certain manner, thevolatilization of the liquid and the consequent expansion or movement ofvessel 1 may be accurately con-. trolled under a wide set of conditions.That is to say, the time required to complete the full stroke of apredetermined movement of vessel 1 may be ascertained and accordinglycontrolled so that the vapor motor may be used in regulators requiringpractically any given set of timed operations.

To accomplish this feature, the windings of heat coil 12 may be sospaced as to *concentrate or localize the heat, either initially orduring subsetguent operation, along tube 2 and thereby e ectvolatilization of a portion of all the liquid in a given time. In thepresent disclosure, it is found that spacing the windin 'of heat coil-12 more closely together at t e top of tube 2 causes a relatively quickvolatilization of the liquid at the upper end of the column so that reid building up of pressure at this point ta es place. Accordingly, thelevel of the liquid 18 rapidly depressed to expand or move a ater volumeof the liquid into the vessel fi accelerate initial expansion. On theother hand this ra id buildin up of pressure is cop inued ter once sarted, so that posit vide the full s roke may be completed in arelatively sho t time.

In the present instance, I have disclosed three times the number ofwindings of heat coil 12 along the up r third of the length of tube 2,and by t is arrangement, I am able to obtain complete expansion ofvessel 1 in one-third of the time which is normal] required where suchspacing is not emp oyed. To illustrate, if tube 2 is three inches inlength, the first inch at the top of tube 2 may be provided with fifteenturns, while the remaining lower two inches may each be provided withfive turns.

It seems that the aforesaid rapid expandg ti n r m em nt of vessel 1 inless continuous vo at coupling 18 with time is the result of morequickly boiling or heatin a small volume of the volatile liquid at areoutset so that with the boilin point once obtained at the level of theco umn .of the li mi in tube 2, more rapid and lization of this columnof liquid can be mainta ed until finally depressed into "the vesse orout of theheatin zone.

t will be unders'tood that the specific example given of the manner inwhich the turnso heat coil 12 are spaced is mere] illustrative of theinvention, and accord ingl may be varied'to meet a given set of conitions in the timing of the movement of vessel 1. V v Y In Fig. 2, theembodiment of the invention illustrates a structure" :lvherein vessel 1is contracted instead of expanded upbn heating of the volatile liquid intube 2. In this instance, vessel 1 is hermeticall sealed to a plate 15lower ed e seating, This sion ing in this chamber will compress vessel 1to move an actuating arm 17 downwardly. Tube 2 may communicate by meansof a chamber 19 at one side of so as to receive a housing 16 ereover andenclosing vessel 1.

chamber 19 between vessel 1 and houshousin 16.

Anot er preferred form of the invention is furnished by housin isreceived so that if desired the fluid in chamber 20 may be used to keepthe volatile.

arrangement provides a closed expan-c 16 so that any increase ofpressure with} k extending outwardly rom its illustrated in Fig. 3. Achamber 20 is 21in which vessel 1.

liquid in vessel 1 in a liquid state and thereby prevent continuedvolatilization thereof' after its level has been depressed intovessel 1. This method of maintaining the predetermined expansion ofvessel 1 may be used where driving the level of the liquid out of theheating zone in tube 2 is not relied upon. In this device, vessel 1 ishermetically sealed at 24 to plate 25. Tube 2 is also carried by plate25 and communicates with vessel 1 by means of a hollow tube 26. Plate 25serves to carry the vapor motor as a unit capable of ready attachment tovarious forms of regulators.

The embodimentshown in Fig. 4 me. be

likewise carried as a detachable unit,-having tube 2 arrangedtransversely however.

to the axis of vessel 1. A coupling 30 coo nects tube 2 with theinterior of vessel 1.

rangeineut. of these sections, it is impossible for this air to travelback into tube 2. The advantage of removing any such air that may be.trapped in the sealin of tube 2 resides in the fact that initial heatingof the liquid is not thereby hindered, inasnulch as the heat may beapplied directly to a greater volume of lit uid.

\Vithout furl ier elaboration, the foregoing will so fully explain thegist of my Invcntion. that others may. by applying current knowledge,readily adopt the same for use under varying conditions of service.without eliminating certain features, which may properly be said toconstitute the essential items of novelty involved, which items areintended to be defined and secured to me by the following claims.

I claim:

1. A heat motor comprising an expansible and contractiblc vessel havinga volatile liquid therein, a heating device therefor and a heat coilwound about said heating device. said heat coil being arranged with thewindings at the top of said heat coil more closely spaced to accelerateinitial heating of said lit uid.

2. A heat motor comprising an expansible and contractible vessel havinga volatile liquid therein, a heating device therefor and a a heat coilwound upon said heating device, the windings of said heat coil along theupper third of the length of said heating device being spaced apartsubstantially onethird the distance between windings along the remainingportion of said heating device whereby to accelerate initial heating ofsaid liquid.

3. A heat motor comprising an expansible. and contractible vessel havinga volatile liquid therein, and a heating device therefor havingprovisions for generating a greater heat within a limited area of saidheating device whereby to accelerate vaporization of said liquid andeffect more rapid expansion of said vessel.

4. A heat motor comprising an expansible and contractible vessel havinga volatile liquid therein, a. heating device therefore. and a a heatcoil wound about said heating device, the windings of said heat coilbeing more closely spaced at the top of said heating device whereby toaccelerate initial heating of said liquid and thereafter more gradualheating to secure rapid expansion of said vessel.

5. A heat motor comprising an expansihlc and contractible vessel and a.tube closed at one end and in communication therewith at the oppositeend. said vessel and said tube having a volatile liquid therein, and anelectrical heat coil wound about said tube. the windings of said heatcoil being spaced more closely together at said closed end wherebyinitially to heat said volatile liquid at a greater rate.

(3. A heat motor comprising a vessel having a volatile liquid thereinand means for heating the liquid for effecting a movement of saidvessel. the arrangement of said heat-- in; means being such that alimited amount of said liquid will be lirst volatilized to acceleratethe initial movement of said vessel.

7. A heat motor comprising an oxpansible and contractihle vessel havingan expansible liquid therein. suitable sup orting means for said vessel.a heating device therefor comprising a substantially closed tubecommunirating at one end with said vessel, and mounting means arranginsaid tube substantially transversely with respect to said vessel.

8. The combination with suitable supporting means. of a heat motormounted thereon and comprising a closed hodv tilled with an expansibleliquid. said body iaving a corrugated section ex ninsihle longitudinallby the pressure of the liquid. a relatively 1nexpansible section havinga heating coil surrounding the same, and a coupling member between saidsections, said coupling member arranging said sections in relative rightangular positions.

In witness whereof, I have hereunto subscribed my name.

LAWRENCE M. PERSONS.

